Evaluation And Performance Of Winter Legume And Legume/Cereal
Mixtures Under Till And No-Till Management
Harold Gerletti
Shamrock Seed Company, 3 Harris Place, Salinas CA 90301
The Sustainable Agriculture Farming Systems (SAFS) Project at
UC Davis proposed and supported this research into alternative
winter crops that could be used in the organic and low-input systems.
In the SAFS project, oats + vetch winter cover crops are harvested
and marketed for green-chop animal feed or as seed crops, thereby
contributing to the economic profitability of the organic and
low-input systems. The SAFS group was interested in investigating
other winter cover crop options which might be more profitable
than oats + vetch. Additionally, a comparison between no-till
and conventional tillage establishment of the winter cover crops
was proposed.
Procedures
Field trials were planted following corn in the companion research
area of the SAFS project over two cropping seasons from Nov. 1993
to June 1995. Six options that had potential as green chop and/or
seed crops were tested the first year. The options tested were:
barley + purple vetch, faba bean + Magnus pea, sweet white lupin,
berseem clover, garbanzo, and oats + purple vetch as the control.
Five options were tested the second year: barley + purple vetch,
faba + Magnus pea, sweet white lupin, maximum organic builder
(a mixture of Cayuse oats, common vetch, Magnus pea, and faba
bean). All the options were tested under no-till and conventional
tillage management. A "Tye" no-till drill was used to
plant the cover crops in both the no-till and tillage treatments.
Results
Garbanzo, berseem clover, and lupin did not perform well in either till or no-till management and no data was collected on them.
Oats + vetch, barley + vetch, faba bean + pea produced marketable green-chop yields under both no-till and till management. The most productive green-chop option tested was maximum organic builder which produced significantly higher yields than any of the other options. Maximum organic builder also received the highest price per ton, making it the most profitable green-chop option tested.
The winter cover crops were allowed to mature and then harvested as seed crops. All options performed well under both till and no-till management. The most profitable seed producers were faba bean + pea followed by oat + vetch. Barley + vetch was the least profitable.
Based on the market prices and the yields obtained in this study, the seed production option was generally more profitable than green-chop option.
Impact of this Work
The results from the two years of field trials investigating the potential of alternative winter cover crops has been encouraging. No-till management, with its inherent benefits for sustainable farming production systems, has proven to be an equally efficient and profitable strategy as conventionally tilled management for producing winter cover crops.
The performance of the successful winter cover crop options was
fairly consistent over two years testing, notwithstanding the
very different weather. This indicates a robust stability and
consistency which would make them low risk choices for farmers.
Publications and Future Plans
The results of this study are included in an M.S. thesis in International
Agricultural Development which will be filed with Graduate Studies
at UC Davis in June 1996.
Cover Crop Research and Education Summaries